Power systems with pulsed loads e.g. large radars typically have a large pulsed load during a radar transmit period, followed by a smaller load during a radar receive period. If the power system has limited energy storage, the system input power profile will follow the pulsed load. Drawing pulsed power from a utility or a generator causes voltage disturbances which can disturb other equipment on the same power distribution bus. The pulsed load can also cause damaging vibrations in the generator and heating of the windings due to the higher rms current of the pulsed input power.
The traditional solution for a pulsed power system is to have a large capacitor bank which provides the peak power to the load during the pulse, and the capacitor bank energy is replenished by charging with a constant current at the mathematical average value of the load current. The power variation at the system input is the product of the charge current and capacitor bank voltage. Even with a constant DC charge current to the system input, the system input power will vary in proportion to the voltage of the capacitor bank, therefore, a <1% voltage droop at the capacitor bank would be required to meet<1% input power variation. The traditional method regulates output voltage to an average constant value using a voltage loop with a time constant much greater than the pulse repetition frequency. The slow loop acts as a low pass filter such that the converter supplies a constant current to the capacitor bank, which attenuates the pulsed load current and therefore has practical limitations in the maximum attenuation.
There is desired a power system that mitigates the effects of the pulsed current load on the input power source.